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07 silverado 1500 fuel issue

When pumping fuel in 07 silverado classic 1500 4.8L the gas pump at the station continues to cut off. took me 20 minutes to pump $50. I now have a check engine light on and the code says it code be the EVAP vent solenoid or the purge solenoid. Truck seems to be running fine other than stronger fuel oder at the exhaust. which solenoid need replaced

It’s not 1965 anymore…Your fuel tank is not capturing and purging (burning) gasoline vapors properly. Few mechanics and fewer vehicle owners understand the complex emissions control systems used today. Your problem is in the EVR system, Enhanced Vapor Recovery. Before you start replacing expensive parts, have a pro determine exactly which parts need to be replaced…

If you have gotten into the habit of squeezing every last drop you can into your fuel tank, overfilling it, that’s a habit you need to break…Usually, (but not always) this is what causes the EVR system to fail…

Ditto what Caddyman said.

check the vapor canister

I have checked the canister and it was completly dry. My truck has sat for long periods at a time while I was in germany.

Germany? Where are you currently located? Perhaps the pump system is different (lacking a vapor recovery system).

Here in the U.S., where most of us are, the systems are set up to allow the vapors in the airspace in the gas tank to be drawn back into the vapor recovery system in the tank pump system when refillling. When you’re driving, expansion of the fuel caused by warming and/or agitation is accomodated by the fumes passing out through the charcoal bed. The charcooal captures the hydrocarbons and the air can pass out to the atmosphere. When you start the engine, the purge solenoid opens the purge valve and the hydrocarbon fumes in the charcoal get drawn into the engine’s intake.

But for this to occur, there are some gravity & fluid operated valves in the tank that need to be in the correct position. One valve transfers the outgoing fume passage from the line back to the gas tank over to the charcoal canister when the tank is full. This, and the change in pressures felt by the pump/vapor recovery system is what causes the pump to shut off.

If this valve is stuck in the position shutting off that return to the pumps’ vapor recovery system, the pump will keep shutting off.

The attached sketch is NOT your system. I only attached it to graphically illustrate the concept. Asl your local dealer’s parts department for a printout of a similar document for your system and you’ll have what you need to begin diagnosis.

I don’t think your problem is in the purge system. I think it’s in the valve in the tank. Or perhaps a kinked line. Perhaps even a plugged hole where the fumes are allowed to travel past the fill pipe to the pump’s vapor recovery system.

http://tijil.org/Scion_Docs/Scion_06_misc_docs/2007sciontc_ncf%20Folder/2azfeemi.pdf

Gas stations no longer capture and recover vapor from vehicle gas tanks, only their own storage tanks…Gone are the elephant snoot nozzles of a few years ago. Today each vehicle captures it’s own fumes as the tank is filled…These vapors are directed into the carbon canister during refueling. There IS a second possibility…Also in the system is a plastic or cork check-ball located in the filler-neck the purpose of which is to prevent spills in the event of a roll-over accident…This ball can get stuck in the closed position as a result of over-filling the tank…This check-ball can sometimes be dislodged and opened by sliding a flexible rod of some sort down the filler neck…One of those fiberglass flag whips used on bicycles works good…or a lightweight fishing rod…